Steam supply equipment



Sept. 22, 1970 5, BLACK STEAM SUPPLY EQUIPMENT Filed Sept. 8, 1969 INV ENTOR. 0657/! All Illll nnl-l'lllll lllll' ATTORNEYS United States Patent 3,529,771 STEAM SUPPLY EQUIPMENT Robert B. Black, 2925 Denver St., Corpus Christi, Tex. 78404 Continuation-impart of application Ser. No. 632,141, Apr. 6, 1967. This application Sept. 8, 1969, Ser.

Int. Cl. B05b 1/24 U.S. Cl. 239-129 6 Claims ABSTRACT OF THE DISCLOSURE GENERAL STATEMENT OF INVENTION AND OBJECTS The present application is a continuation-in-part of my copending application Ser. No. 632,141 filed Apr. 6, 1967, issued May 12, 1970, as Pat. No. 3,511,440, and is particularly concerned with certain features of improvement in equipment of the kind disclosed in said prior application.

This invention relates to steam supply equipment and especially to equipment for producing, handling and delivering through a discharge orifice or nozzle to a point of use a pressurized hot fluid mixture comprising the gaseous products of combustion of a fuel serving as a gaseous carrier for steam or particles of water, or both steam and water. The invention is particularly useful in connection with cleaning equipment and for this purpose the invention also preferably provides for the delivery of a detergent, along with the steam or particles of water. For purposes of illustration the invention is hereinafter described with special reference to its use in connection with cleaning equipment, but it is to be understood that many of the features, objects and advantages are of use in many other systems for producing, handling and delivering to a point of use a pressurized stream of combustion products carrying at least steam or water particles, or both.

As is brought out in my copending application above identified, pressurized cleaning systems of known types commonly include a steam generator comprising extended lengths of tubing in the form of coils located in heat exchange relation to a combustion chamber. By force feeding water into the coils, steam is generated under pressure and then delivered to a discharge orifice or pressure nozzle through a flexible hose so that the nozzle may be directed to the desired areas to be cleaned. Equipment of this type is commonly employed in car wash establishments, automotive service stations, radiator and air conditioning repair shops, and other types of businesses where cleaning equipment is needed. Detergent is usually introduced into the system so that the nozzle delivers both hot detergent solution and steam to the point of use.

Prior art systems of the kind referred to above are subject to numerous disadvantages, including the fact that with the steam coil systems substantial thermal losses occur primarily due to inefiicient heat transfer. The prod- 3,529,771 Patented Sept. 22, 1970 ice nets of combustion employed to 'heat the coils are thus discharged to the atmosphere while still retaining a large amount of heat. Moreover, the prior art coil systems result in discharge to atmosphere of noxious or even toxic gases from the combustion chamber in the environmental area because of incomplete combustion. Still further, the steam generating coils are very heavy and bulky, frequently comprising as muc'h as several hundred feet of metal tubing, are subject to soot and scale problems (which contribute to further heat losses), and are also susceptible to rapid deterioration as a result of corrosion and rust.

The prior art systems are thus characterized by ineflicient combustion and by ineflicient utilization of the heat of combustion, and with these major deficiencies in mind, the principal objectives of the present invention are the attainment of virtually perfect combustion, combined with close to complete absorption of the heat of combustion for cleaning purposes.

In common with the arrangement described in my copending application above identified, the present invention also provides a steam supply or steam cleaning system in which fuel is continuously and efliciently burned at elevated pressures in a combustion chamber after which water is injected into the hot products of combustion prior to delivery thereof to a discharge or pressure nozzle at the point of use. By the system of the present invention, a very large heat economy is effected in consequence of use of the combustion products as a portion of the pressurized hot fluid medium being delivered through the nozzles at the point of use. Moreover, in accordance with the invention, the combustion is effected under conditions which prevent the formation of noxious or toxic fumes or gases normally associated with the steam coil cleaning systems. In a typical operation according to the present invention, the gaseous products of combustion, prior to the introduction of water or detergent, comprise about 13.2% carbon dioxide, 0.2% oxygen, and about 86.6% of nitrogen and other inert gases, including water vapor.

According to the present invention the steam supply system still further includes an accumulator for receiving the products of combustion and steam, and also detergent when used, at times when the discharge nozzle is shut 01f. The accumulator is arranged to provide for the separation of hot gaseous products of combustion from the water and to maintain the products and water under pressure. Provision is also made for separate delivery of the Water and gaseous products from the accumulator, the water being delivered through a controllable nozzle so that it will reflas into steam upon discharge to the atmosphere, thereby providing in the system a source of steam (and detergent if used), without admixture with gaseous products of combustion. The gaseous products are discharged from the accumulator separately from the water and the invention contemplates discharge of the gaseous products through a heat exchanger for heat exchange with the feed water to be introduced into the combustion products as they leave the combustion chamber.

In view of the foregoing, the accumulator provided in accordance with the present invention utilizes the pressure of the system for the discharge of the water separated in the accumulator from the combustion products, and also provides for recovery of the heat of the combustion products in consequence of the heat transfer with the feed or make up water to be injected into the combustion products.

Description of drawing How the foregoing and other objects and advantages are attained will appear more fully from the following description referring to the accompanying drawing, in

The major components of the system include the combustion chamber C, the air compressor P, the motor M, nozzles N, N, the fuel supply tank F, detergent supply tank D, and the accumulator A with which another nozzle Z is associated. Before considering the interconnection of these various components, attention is first directed to the fact that in the schematic view of this figure the combustion chamber C is illustrated diagrammatically. The construction of this combustion chamber need not be considered herein, but for details of construction reference may be made to my copending application above identified.

The combustion chamber is preferably of double walled construction in order to provide a jacket 7 through which a cooling medium may be circulated. Air is introduced into the combustion chamber as indicated at 19. Fuel is also introduced into the combustion chamber as indicated at 10.

Toward the opposite end of the combustion chamber an outlet 16 is provided, this outlet serving as the initial discharge for the products of combustion from the combustion chamber. Preheated water is introduced into the stream of hot combustion products flowing through the discharge 16 by means of a nozzle 17.

The preheated water for introduction through the nozzle 17 is derived from the connection 18 communicating with the jacket space surrounding the combustion chamher. The inlet '19 for the water introduced into the jacket 7 of the combustion chamber derives its supply from the cooling jacket 36 surrounding the cylinders of the compressor P, these parts all being diagrammatically indicated here because the details thereof form no part of the present invention per se. Various structural parts referred to just above and also herebelow are similarly identified in my copending application above identified, to which reference may be made for further details.

In the diagram of the figure, the fuel is supplied from the tank F through the fuel supply line 20 having a solenoid operated shut oif valve 21 controlled by the switch 22. In addition the fuel supply line is provided with a controllable needle valve 23. The air for combustion is delivered from the compressor P through the connection 24, which communicates with the connection 11 in turn communicating with the inlet 10. An air pressure gauge line 25 extends from the connection 11 to the pressure gauge 26.

The compressor itself may be of any known construction, for instance a V-4 cylinder compressor. The cylinders of the compressor are provided with an air inlet 28, and the compressor is driven by an electric motor M which may also serve to drive the Water pump 29.

As shown in the figure, the water pump receives its supply through the line 30 which is connected with the heat exchanger 68 with which the water supply line 69 is also connected. The association of this heat exchanger with the accumulator A will be described more fully hereinafter.

From the pump 29 the water is delivered through the line 34 provided with an adjustable (preferably gate) valve 35. The water line 34 delivers the water to the cooling jacket 36 associated with the cylinders of the compressor P. After flowing through the compressor jacket the water is delivered through the connection 19 above referred to into the cooling jacket 7 surrounding the combustion chamber. As above mentioned, the water leaves the jacket for the combustion chamber through the fitting 18 and is introduced into the stream of combustion products by the nozzle 17. The flow from the fitting 18 to the nozzle 17 is controlled by the solenoid operated valve 37 which is controlled by the switch 38.

The discharge 16 is connected by means of connection 42 with a T-fitting 70 which in turn is connected with 4 the fitting 71 from which the branch lines 50 and 51 are extended to the discharge or pressure nozzles N, N.

A temperature gauge is provided and has a tempera ture responsive capsule 45a associated with the offtake 16, thereby providing a temperature reading of the gaseous mixture in the discharge.

The pressure nozzles are of known construction and need not be considered in detail herein, but it is noted that each one of them is provided with a discharge orifice, for instance of /s" or A" diameter and also with a manual valve 52 which closes when released.

As seen in the figure, detergent is fed into the system from the detergent supply tank D through a connection 54 having a manual shut off valve 54a and a controllable needle valve 55. The detergent supply line 54 introduces the detergent into the system through the fitting 71 from which the nozzle supply lines and 51 extend.

Attention is now called to the provision of an air pressure line 56 which extends from the air supply connection 11 and which has branches 57 and 58 communicating respectively with the fuel and detergent supply tanks F and D. These connections make possible the use of the compressor for pressurizing the fuel and detergent in the supply tanks in the manner described in my copending application above identified.

The equipment may also include provision for pressurizing the fuel and detergent tanks from another source of air under pressure, for instance from the source indicated at 59 which is connected with the line 56. With this system it is preferred to employ a pair of check valves 60 and '61 in the line 56 and to arrange the connection 59 so that air introduced therefrom will enter the line 56 between the check valves 60 and 61. The independent air supply line 59 desirably also has a shut off valve 62. In this way the fuel and detergent supply tanks may alternatively be pressurized either by the compressor P or by an independent source of air or other gas under pressure, such as is commonly available in many shops, service stations, and the like. If desired, one or the other of these pressurizing systems may be omitted from the equipment.

The motor M is adapted to be controlled by a switch 63, this switch also serving to control the ignition system indicated diagrammatically at 64 which supplies the desired current for the ignition device 65. The type of ignition system employed will depend upon the type of fuel being used. In the event of use of a gaseous or volatile fuel such as gasoline, a spark plug will ordinarily be used as the device indicated at 65, and in this case device 64 will be designed to supply the required high voltage current for spark plug operation. On the other hand in the event of employment of diesel oil as fuel, a glow plug may be employed at 65, and in this case the device 64 will be designed to provide the desired low voltage but high amperage current adapted to effect continuous heating of the ignition element of the glow plug.

Instead of employing a detergent recovery system of the kind disclosed in my copending application identified above, which is open to the atmosphere and therefore operates at atmospheric pressure, the present invention contemplates the use of an accumulator A in the form of a pressure vessel having lagging or insulation indicated at 72 adapted to prevent substantial heat loss. When the noz zles N, N are both closed, the gaseous products of combustion together with the steam or water particles will pass from the connection 42 through the T-fitting and through the check valve 73 and line 74 into the lower portion of the accumulator A. In the accumulator the gaseous products of combustion will separate out and rise to the top, the water remaining in the lower portion of the vessel. At the top of the accumulator A the gas discharge line 75 delivers the gaseous products of combustion through the relief valve 76 into the heat exchanger 68, for ultimate discharge through the outlet 77. In the heat exchanger 68 the gaseous products are brought into heat exchange relation with the feed water which is introduced at 69, thereby recovering heat from the combustion products before discharge thereof to atmosphere. The relief valve 76 in a typical installation will be set to open at a pre-set pressure, for example, 80100 p.s.i. A pressure gauge 78 is desirably associated with the gas offtake line 75.

An oiftake 80 is provided at the bottom of the accumulator through which the water (and detergent if used) is delivered under pressure to the nozzle Z. This nozzle may be of the same general construction as described above with reference to the nozzles N, N, including a shut off valve 52 adapted to close when released. At the discharge end 81 of the nozzle Z, an orifice is preferably provided of a size from about 0.012 (#30) to about 0.0180" (#18), this orifice being located at the base end of the fan-shaped nozzle tip. The use of a small opening or orifice at this point will aid in maintaining full pressure in the accumulator on the upstream side of the orifice, but will release a certain percentage of the superheated liquid (or detergent solution where detergent is, employed) which will flash into steam as it escapes into the fanshaped nozzle at the downstream side of the orifice. This will produce a fan-shaped discharge stream which is efiective for various types of cleaning purposes.

Operation To consider a typical starting operation and also the continued normal operation of the system, it is here first assumed that the fuel and detergent tanks F and D have been pressurized, in the manner referred to above. With the nozzles N, N closed the accumulator A will be charged and the relief valve 76 will permit blow-01f of combustion products during start-up. When the desired combustion conditions are attained and remain stable, the manual valves 52, 52 at the nozzles may be opened for delivery of the gaseous cleaning medium to the desired point of use.

Detergents may be introduced into the system by opening valve 55 and adjusting that valve to provide the quantity of detergent needed for any particular cleaning operation.

When the nozzle valves 52, 52 are both closed, steam and detergent will flow through the pipe 74 to the accumulator A in which detergent and water separate from the gases and accumulate in the bottom of the vessel. The gases will accumulate in the top of the vessel and the pressure will build up to the point represented by the predetermined relief pressure of the valve 76, at which time gases will be discharged through the heat exchanger 68. When the valves 52 of the nozzles N, N are again opened, the check valve 73 will prevent discharge of liquid from the accumulator A.

Liquid (and detergent when used) may be delivered from the accumulator A through the nozzle Z by opening the valve 52 of that nozzle and thereby causing discharge through the small orifice adjacent the delivery end of the nozzle. This arrangement thus provides not only for delivery through nozzles N, N of steam (and detergent if used) in a stream of combustion products, but also provides for delivery of steam (and detergent if used) without the presence of combustion gases, through the nozzle Z. For certain purposes it is preferred to have the combustion gases present in the discharge and for other purposes it is preferred not to have those gases present, and the system of the present invention has great flexibility because it provides alternatively for one or the other, or both types of discharge.

The use of the accumulator is not only desirable for the reasons just pointed out but in addition because the accumulator, in effect, makes possible the recovery of both pressure and heat which would otherwise be lost. The transfer of heat to the make up or feed water in the heat exchanger 68 is especially advantageous as this preheats the water to some substantial degree even in advance of 6 the flow of that water through the jacket 36 of the compressor P and in advance of the flow of that water through the jacket 7 of the combustion chamber C. Because of these several stages of water preheating, by the time the water is injected into the stream of combustion products in the offtake 16 from the combustion chamber, the temperature of the water is already elevated to such an extent that flashing into steam is greatly facilitated.

Other means for effecting preheating of the water may be used in combination with a heat exchanger such as indicated at 68, including, for example, a preheating stage in the cooling system of an internal combustion engine used (instead of motor M) to drive the compressor, for instance in the manner illustrated in FIG. 6 of my copending application above identified.

With regard to the injection or introduction of the water, it is first noted that water is preferably introduced through a nozzle adapted to effect spraying or atomization of the water. The quantity of water may be varied widely, with resultant variation in the amount and condition of the water or moisture present in the system. First, it is of course possible to use the system with relatively little water, but ordinarily, the quantity of water introduced would not be less than that quantity which could be completely converted to steam, by flash steam generation, as the incoming water meets the high temperature stream of combustion products. Increase in the amount of water beyond that quantity will result in the presence of some water as such in fine particle form and, for most cleaning purposes, it is preferred that the quantity of water introduced be more than that quantity which would result in conversion of all of the water to steam, so that both water and steam will be present. Indeed for many purposes it is preferred that the Water content predominate over the amount of steam present, and this can readily be accomplished by increasing the quantity of hot water introduced.

In connection with the compressor P, it is first pointed out that where an adequate compressed air supply is otherwise available, the compressor may be omitted. However, in a typical installation incorporating a compressor, the air which is taken into the compressor through the inlet 28 should preferably be compressed to at least several atmospheres pressure, a range of pressure of from about 50 to about 300 p.s.i. being suitable and this will be an important factor in determining the pressure of operation of the system. Assuming that the operating pressure is about 100 p.s.i. in a typical installation, this increase in pressure of the air from atmospheric pressure raises the temperature of the air from normal atmospheric temperature or R), up to about 275 F. This preheating of the air is of course advantageous in the attainment of the desired combustion temperature.

Any of a variety of fuels may be employed in the system, such as gasoline, kerosene, diesel oil, natural gas, propane fuels and other hydrocarbon fuels.

I claim:

1. Steam supply equipment including, in combination with a discharge nozzle, a combustion chamber having inlet means for fuel and air and an outlet with a connected conduit for discharging a stream of gaseous products of combustion, means for delivering air and fuel under pressure through the inlet means to the combustion chamber, means for delivering water into the stream of combustion products for flash steam generation and for delivery of the steam with the combustion products to the discharge nozzle, an accumulator, a connection extended from said conduit to the accumulator, a pressure operated valve providing for delivery of steam and gaseous products of combustion from said conduit into the accumulator when the pressure in said conduit exceeds a predetermined value, a pressure responsive valve for discharging gaseous products of combustion from an upper portion of the accumulator, and means for separately discharging water under pressure from a lower portion of the accumulator.

2. Equipment according to claim 1 and further including a heat exchanger for transferring heat from the gaseous products of combustion discharged from the upper portion of the accumulator to the water delivered into the stream of combustion products discharged from the combustion chamber.

3. Steam supply equipment including, in combination with a discharge nozzle, a combustion chamber having inlet means for fuel and air and an outlet with a connected conduit for discharging a stream of gaseous products of combustion, means for delivering air and fuel under pressure through the inlet means to the combustion chamber, means for delivering water into the stream of combustion products for flash steam generation and for delivery of the steam with the combustion products to the discharge nozzle, a closed vessel for accumulating steam and gaseous products of combustion under pressure, a connection extended from said conduit to said vessel, means providing for delivery of steam and gaseous products of combustion from said conduit into the vessel, means for discharging gaseous products of combustion from an upper portion of said vessel, and means for separately discharging Water under pressure from a lower portion of said vessel.

4. Equipment according to claim 3 and further including a jacket surrounding at least part of the combustion chamber, means for circulating water to be delivered into the combustion products through said jacket, and a heat exchanger for transferring heat from the gaseous products discharged from the upper portion of said vessel to the water to be circulated through said jacket.

5. Steam supply equipment including, in combination with a discharge nozzle having a shut-off valve, a combustion chamberhaving inlet means for fuel and air and an outlet with a connected conduit for discharging a stream of gaseous products of combustion, means for delivering air and fuel under pressure through the inlet means to the combustion chamber, means for delivering water into the stream of combustion products for flash steam generation and for delivery of the steam with the combustion products to the discharge nozzle, an accumulator, a connection extended from said conduit to the accumulator, a pressure operated valve means providing for delivery of steam and gaseous products of combustion from said conduit into the accumulator when the nozzle shut-off valve is closed, means for discharging gaseous products of combustion from an upper portion of the accumulator, and means for separately discharging water under pressure from a lower portion of the accumulator.

6. Equipment according to claim 5 in which the means providing for delivery of steam and gaseous products into the accumulator comprises a check valve providing against reverse fluid fiow from the accumulator.

References Cited UNITED STATES PATENTS 1,825,131 9/1931 Shepherd 239129 X 2,345,614 4/1944 Malsbary et al. 239-307 X 2,919,070 12/1959 Arant 239-304 X M. HENSON WOOD, JR., Primary Examiner JOHN I. LOVE, Assistant Examiner US. Cl. X.R. 239304 

